Whooping crane flock size estimated smaller than last year

Feb 17, 2013 | Victoria Advocate by Dianna Wray | Related Press

After weeks of waiting, the U.S. Fish and Wildlife Service has issued its first count of the whooping crane flock using a new estimation technique.

The preliminary analysis estimates the flock to be made up of about 257 birds with a 95 percent confidence interval that ranges between 178 and 362 whoopers, according to a release issued Friday.

This is a disappointing development for longtime whooping crane enthusiasts, Chester McConnell, a trustee emeritus with the Whooping Crane Conservation Association, said.

“We watch these numbers religiously, and we were hoping the flock would reach 300 birds in the next few years, but now they’re saying there are 40 less birds,” McConnell said.

The counting system was changed after Tom Stehn, the whooping coordinator for 29 years, retired last year, and there was no one with Stehn’s institutional knowledge to replace him, McConnell said.

“Tom became very proficient and was counting what he and we believed was a total count with five to seven flights over the territories, knowing the birds tend to stay in one place,” McConnell said. “He had the type of skill and knowledge base that we could rely on his counts.”

However, after Stehn retired, those who replaced him didn’t have the skill or the knowledge to count the birds, leading the group to change its procedure. It now gathers enough information on survey flights to estimate the size of the flock instead of a direct head count.

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